| 1. |
- Shah, Aqeel Ahmed, et al.
(författare)
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Facile synthesis of copper doped ZnO nanorods for the efficient photo degradation of methylene blue and methyl orange
- 2020
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Ingår i: Ceramics International. - Oxford : Elsevier. - 0272-8842 .- 1873-3956. ; 46:8, part A, s. 9997-10005
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Tidskriftsartikel (refereegranskat)abstract
- In this study, zinc oxide (ZnO) nanorods are doped with copper by low temperature aqueous chemical growth method using different concentrations of copper 5 mg, 10 mg, 15 mg and 20 mg and labeled as sample 1, 2, 3 and 4 respectively. The morphology and phase purity of nanostructures was investigated by scanning electron microscopy, and powder X-ray diffraction techniques. The optical characterization was carried out through UV–Vis spectrophotometer. The band gap of coper doped ZnO has brought reduction at 250–600 nm and it indicates the fewer time for the recombination of electron and hole pairs, thus enhanced photo degradation efficiency is found. ZnO exhibits nanorods like shape even after the doping of copper. The photo degradation efficiency for the two chronic dyes such as methyl orange MO and methylene blue MB was found to be 57.5% and 60% respectively for a time of 180 mints. This study suggests that the copper impurity in ZnO can tailor its photocatalytic activity at considerable rate. The proposed photo catalysts are promising and can be used for the waste water treatment and other environmental applications. © 2019 Elsevier Ltd and Techna Group S.r.l.
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| 2. |
- Shah, Aqeel Ahmed, et al.
(författare)
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Tin as an Effective Doping Agent into ZnO for the Improved Photodegradation of Rhodamine B
- 2021
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Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2529-2537
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Tidskriftsartikel (refereegranskat)abstract
- We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn) using different concentrations of 25, 50, 75 and 100 mg of tin chloride. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. The doped materials were then investigated for their photo catalytic degradation of environmental pollutant Rhodamine B. The performance of doped ZnO is compared with the pristine ZnO. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Photo catalytic activity of rhodamine B was investigated under UV light and a maximum degradation efficiency of 85% was obtained. The optical property reveals the reduction in band gap of upto 17.14% for 100 mg Sn doped ZnO. The degradation is followed by the pseudo order kinetics. The produced results are unique in terms of facile synthesis of Sn doped ZnO and excellent photo degradation efficiency, therefore these materials can be used for other environmental applications.
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| 3. |
- Bhatti, Muhammad Ali, et al.
(författare)
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Efficient photo catalysts based on silver doped ZnO nanorods for the photo degradation of methyl orange
- 2019
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Ingår i: Ceramics International. - Oxford : Elsevier. - 0272-8842 .- 1873-3956. ; 45:17, Part B, s. 23289-23297
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the doped ZnO nanorods with silver (Ag) as photosensitive material are prepared by the solvothermal method. The structural and optical characterization is carried out by the scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and UV–visible spectroscopy. The use of Ag as dopant did not alter the morphology of ZnO except sample 4 which has flower like morphology. The Ag, Zn and O are the main constituent of doped materials. The XRD revealed a hexagonal phase for ZnO and cubic phase for silver and confirmed the successful doping of Ag. The photocatalytic activity of Ag doped ZnO nanorods was investigated for the photo degradation of methyl orange. The photocatalytic measurements show that 88% degradation of methyl orange by the sample 4 within the 2 h of UV light treatment (365 nm) is significant advancement in the photocatalyst and provide the inexpensive and promising materials for the photochemical applications. © 2019 Elsevier Ltd and Techna Group S.r.l.
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| 4. |
- Bhatti, Muhammad Ali, et al.
(författare)
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Enzymes and phytochemicals from neem extract robustly tuned the photocatalytic activity of ZnO for the degradation of malachite green (MG) in aqueous media
- 2021
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Ingår i: Research on chemical intermediates (Print). - : SPRINGER. - 0922-6168 .- 1568-5675. ; 47:4, s. 1581-1599
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Tidskriftsartikel (refereegranskat)abstract
- The malachite green (MG) is very difficult to degrade in water; thus, it needs an efficient photocatalyst. In this study, neem extract was used to tune the surface and crystal properties of ZnO nanostructures for the photodegradation of MG. The biosynthesized ZnO samples were prepared by hydrothermal method in the presence of 5, 10 and 15 mL of neem extract. The structural characterization has shown nanoparticle like morphology of ZnO as revealed by scanning electron microscopy (SEM) and hexagonal phase was confirmed by powder X-ray diffraction (XRD) technique. The XRD analysis has shown a shift in the 2 theta towards lower angle for ZnO with increasing amount of neem extract. Also, the crystallite particle size of ZnO was decreased with increasing neem extract. The UV-visible spectroscopy has shown the decrease in the optical band gap of ZnO, and the lowest band gap is possessed by ZnO sample produced with 15 mL of neem extract. The ZnO sample obtained with 15 mL of neem extract has shown approximately 99% degradation efficiency for MG for 70 min in aqueous solution. The superior photocatalytic activity of ZnO sample with 15 mL of neem extract could be attributed from the decrease in charge recombination rate due to the decreased optical band gap and particle size.
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| 5. |
- Bhatti, Muhammad Ali, et al.
(författare)
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Low Temperature Aqueous Chemical Growth Method for the Doping of W into ZnO Nanostructures and Their Photocatalytic Role in the Degradration of Methylene Blue
- 2022
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Ingår i: Journal of cluster science. - : SPRINGER/PLENUM PUBLISHERS. - 1040-7278 .- 1572-8862. ; 33:4, s. 1445-1456
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Tidskriftsartikel (refereegranskat)abstract
- In this research work, we have produced tungsten (W) doped ZnO nanostructures via low-temperature aqueous chemical growth method. The morphology, crystal arrays and composition was investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and energy dispersive X-rays (EDX) respectively. The SEM results indicate the nanowire morphology before and after the doping of W into ZnO and XRD study has shown the hexagonal crystallography of W doped ZnO samples. The EDX study has confirmed the successful doping of W into ZnO crystal lattices. The photodegradation performance of methylene blue was evaluated with W doped ZnO samples and pristine ZnO in aqueous solution. The measured degradation efficiencies for the different W doped ZnO samples were 5 wt%, 10 wt%, 15 wt% and 20 wt% at pH 5 are 87.8%, 92.3%, 92.8% and 96.9%), at pH 9 (72.1%, 90.7%, 92.1%, and 96.4%) and at pH 11 (80%, 85%, 87% and 89%) for the time interval of 90 min respectively. The pH of dye solution has significant effect on the degradation efficiency. These findings show that the W doped ZnO samples have superior degradation efficiency of 96.6% in a very short interval of time. The swift degradation kinetics for the W doped ZnO samples is attributed to the reduction in the energy band gap, decrease in particle size, enhanced surface area, decrease in the recombination rate and foster charge separation process. The obtained results are exciting and providing efficient earth-abundant photocatalysts for the energy and environmental purposes.Kindly confirm the Given names and Family names for all the authors.They are correct.
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| 6. |
- Bhatti, Muhammad Ali, et al.
(författare)
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TiO2/ZnO Nanocomposite Material for Efficient Degradation of Methylene Blue
- 2021
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Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2511-2519
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Tidskriftsartikel (refereegranskat)abstract
- In this research work, we have produced a composite material consisting titanium dioxide (TiO2) and zinc oxide (ZnO) nanostructures via precipitation method. Scanning electron microscopy (SEM) study has shown the mixture of nanostructures consisting nanorods and nano flower. Energy dispersive spectroscopy (EDS) study has confirmed the presence of Ti, Zn and O as main elements in the composite. X-ray diffraction (XID) study has revealed that the successful presence of TiO2 and ZnO in the composite. The composite material exhibits small optical energy band gap which led to reduction of the charge recombination rate of electron-hole pairs. The band gap for the composite TiO2/ZnO samples namely 1, 2, 3 and 4 is 3.18, 3.00, 2.97 and 2.83 eV respectively. Small optical bandgap gives less relaxation time for the recombination of electron and hole pairs, thus favorable photodegradation is found. The degradation efficiency for the TiO2/ZnO samples for methylene blue in order of 55.03%, 75.7%, 85.14% and 90.08% is found for the samples 1, 2, 3 and 4 respectively. The proposed study of titanium dioxide addition into ZnO is facile and inexpensive for the development of efficient photocatalysts. This can be capitalized at large scale for the energy and environmental applications.
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| 7. |
- Khokhar, Shams Parveen, et al.
(författare)
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An Efficient Nickel Sulfide@NiO Nanocomposite Catalyst with High Density of Active Sites for the Hydrogen Evolution Reaction in Alkaline Media
- 2021
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Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2520-2528
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Tidskriftsartikel (refereegranskat)abstract
- Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are highly vital to design practical and environmentally friendly water splitting devices. In this study, we present an optimized strategy for the development of active catalysts for hydrogen evolution reaction HER. The composite catalysts are prepared with the nanosurface of NiO for the deposition of NiS by hydrothermal method. In alkaline electrolyte, the NIS/NiO nanocomposite has shown excellent catalytic HER properties at the low onset potential and small Tafel slope of 72 mV dec(-1). A current density of 10 mA/cm(2) is achieved by the nanocomposite obtained with 0.4 gram of NiO as nanosurface for the deposition of NiS (sample 4) at the cost of 429 mV versus RHE. The sample 4 carries more active sites that allow it to act as excellent HER catalyst. Based on this study, we conclude that increasing the nickel oxide content into composite sample facilitates the HER process. Additionally, a long term HER stability for 10 hours and good durability is also demonstrated by the sample 4. Our findings reveal that the optimization of nickel oxide content in the preparation of catalyst leads to the excellent HER activity for the design of practical water splitting devices and other related applications.
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